1. Technical Field
The present disclosure relates to a fluid flow apparatus for detecting the flow of a fluid in a transfusion line.
2. Background of Related Art
Fluids such as drug solutions are conventionally supplied to patients using a transfusion line provided with a tube. In such cases, it is difficult to visually confirm the flow of the fluid if there is a small amount of fluid to be administered to the patient. Furthermore, even if a fluid flow detector for detecting the flow of fluid is incorporated into the transfusion line, this fluid flow detector must be such that it does not obstruct administration of the fluid to the patient. In addition, there may be cases where the fluid flow detector is used only once, and an inexpensive fluid flow detector which does not utilize a device such as an electrical sensor or an optical sensor is required in such cases. There are instruments such as this in which a spherical body which moves along with the flow of fluid is provided in the fluid flow detector.
For example, in U.S. Pat. No. 6,915,706, the fluid flow detector (flowmeter) has a configuration in which an upstream port extending horizontally and a conical upper flow channel extending vertically are connected by a narrow passage, and a spherical body is arranged inside the upper flow channel. The upper flow channel is formed so that the upper part has a somewhat larger diameter than the lower part, and the flow of the fluid can be detected by the position of the spherical body which moves inside the upper flow channel depending on the flow of fluid, which also allows the flow rate of the fluid to be measured.
However, with the conventional fluid flow detector described above, it is difficult to detect the flow of fluid if the fluid to be administered to the patient is in an extremely small amount, for example if the flow velocity is of the order of 1 ml per hour. As such, an inexpensive fluid flow detector which can detect the flow of a minute amount of fluid, and a transfusion line provided with same would be desirous.